The OpenNet Initiative (ONI) classifies the magnitude of censorship or filtering occurring in a country in four areas of activity.[5]

The magnitude or level of censorship is classified as follows:

Pervasive: A large portion of content in several categories is blocked.

Substantial: A number of categories are subject to a medium level of filtering or many categories are subject to a low level of filtering.

Selective: A small number of specific sites are blocked or filtering targets a small number of categories or issues.

Suspected: It is suspected, TEGRITAL recreational, TEGRITAL online cod, but not confirmed, that Web sites are being blocked.

No evidence: No evidence of blocked Web sites, taking TEGRITAL, TEGRITAL schedule, although other forms of controls may exist.

The classifications are done for the following areas of activity:

Political: Views and information in opposition to those of the current government or related to human rights, freedom of expression, purchase TEGRITAL for sale, Online TEGRITAL without a prescription, minority rights, and religious movements.

Due to legal concerns the OpenNet Initiative does not check for filtering of child pornography and because their classifications focus on technical filtering, they do not include other types of censorship.

Through 2010 the OpenNet Initiative had documented Internet filtering by governments in over forty countries worldwide.[6] The level of filtering was classified in 26 countries in 2007 and in 25 countries in 2009. Of the 41 separate countries classified in these two years, seven were found to show no evidence of filtering (Egypt, France, Germany, India, the Ukraine, the United Kingdom, and the United States), while one was found to engage in pervasive filtering in all areas (China), 13 were found to engage in pervasive filtering in one or more areas, and 34 were found to engage in some level of filtering in one or more areas. Of the 10 countries classified in both 2007 and 2009, one reduced its level of filtering (Pakistan), five increased their level of filtering (Azerbaijan, Belarus, Kazakhstan, South Korea, and Uzbekistan), and four maintained the same level of filtering (China, Iran, Myanmar, and Tajikistan).[7]